Article excerpt

In 2008 NICE guidance recommended the identification and treatment of Attention Deficit Hyperactivity Disorder (ADHD) in adults. Previously, diagnosis and treatment of this condition had mainly been confined to children and young people. Dr Tamsin Newlove-Delgado and Professor Ken Stein from University of Exeter explain why adult ADHD is important and what the implications are for health improvement, commissioning and providing evidence based services

Attention Deficit Hyperactivity Disorder (ADHD) is a neurodevelopmental disorder, with symptoms of inattention, hyperactivity and impulsivity causing significant impairment in functioning. The diagnostic criteria for ADHD currently require that symptoms must have been present before the age of seven years, and be apparent in more than one setting.

There is no single cause; instead the condition appears to result from a complex interaction of genetic and environmental factors.1 ADHD is estimated to affect 3-5% of children of school age in the UK.1,2

Does ADHD exist in adults?

Few studies have followed up young people with ADHD beyond the age of 25. A meta-analysis of data from follow-up studies suggested that although the rate of persistence of ADHD meeting the full diagnostic criteria at age 25 was only 15%, the persistence of symptoms was much higher at around 40-60%.3 Therefore, although the prevalence of ADHD certainly declines with age, a significant proportion of adults have still been found to be affected.

ADHD in adults remains the subject of some debate, given the high rate of co-morbidities and the difficulty in distinguishing normal symptoms from pathological ones. However, in 2008 the National Institute for Health and Clinical Excellence (NICE) reviewed the evidence on adult ADHD, recommending recognition of the condition and establishment of services for assessment and management, with stimulant medication as the first-line treatment for adults with either moderate or severe levels of impairment.2

How many adults might suffer with ADHD?

A meta-analysis of world literature produced a pooled prevalence estimate of 2.5%.4 The UK 2007 Adult Psychiatric Morbidity Survey5 used the six item Adult ADHD Self Report Scale (ASRS) to screen the sample for ADHD symptoms. Using this scale 8.2% of adults scored four or more, which was considered to warrant clinical assessment, and 0.6% scored all six, indicating a high likelihood of a positive diagnosis. NICE have estimated the number of men with ADHD at over 300,000 in England, and the number of women at over 80,000,6 indicating that there is a considerable population likely to be affected.

Impact of adult ADHD Higher risk of other psychiatric disorders

Adults with ADHD are at increased risk for other psychiatric disorders. Over a lifetime, it is estimated that over threequarters of those with ADHD will have a psychiatric co-morbidity;7 with depression and anxiety being most common.

Substance misuse and smoking

Substance misuse affects up to half of adults with ADHD.7 A significant proportion of those in contact with substance misuse services also have ADHD symptoms. High rates of smoking (up to 40%) in ADHD8 may be explained by genetic influences or self-medication with nicotine: the condition is also linked with earlier initiation of smoking and difficulty in quitting.9

Accidents

Studies have reported that adolescents and adults with ADHD are more likely to be involved in road traffic collisions, to be stopped for speeding, and to report losses of concentration and control whilst driving.10 Similarly, both children and adults with ADHD appear to have more accidents and injuries in general, possibly due to impulsivity and risktaking behaviours.11

Educational and occupational underachievement

Adults with ADHD experience higher job turnover and more periods of unemployment. A recent European study found they were twice as likely to be unemployed. …